Capacitive gap sensor ring for an input device

ABSTRACT

An input mechanism for a portable electronic device includes a rotational manipulation mechanism, such as a cap or shaft. The input mechanism also includes a sensor having first capacitive elements coupled to the manipulation mechanism, second capacitive elements, and a dielectric positioned between the first and second capacitive elements. Movement of the manipulation mechanism alters the positions of the first and second capacitive elements with respect to each other and is determinable based on capacitance changes resulting therefrom. In some implementations, the second capacitive elements may be part of an inner ring or partial ring nested at least partially within an outer ring or partial ring.

FIELD

The described embodiments relate generally to input devices. Moreparticularly, the present embodiments relate to a capacitive sensor thatcan detect multiple types of motion of an input device.

BACKGROUND

Electronic devices include a variety of different input and/or outputdevices for receiving input from and/or providing output to users.Examples of input and/or output devices include keyboards, touchscreens, displays, joysticks, microphones, speakers, watch crowns,trackpads, track balls, and so on.

Some input devices include a moveable member and one or more sensors orother components that detect the movement of the moveable member. Forexample, keyboards may include a number of keycaps that can be pressedto activate one or more switches. Activating a switch may provide inputto the electronic device.

SUMMARY

An input mechanism for a portable electronic device includes amanipulation mechanism, such as a cap or shaft that is moveable inmultiple directions. The input mechanism also includes capacitivesensors arranged in multiple planes with respect to the manipulationmechanism that are associated with the multiple directions of movement.The capacitive sensors have first capacitive elements coupled to themanipulation mechanism, second capacitive elements, and a dielectricpositioned between. Movement of the manipulation mechanism alters thepositions of the first and second capacitive elements with respect toeach other. The movement is determinable based on capacitance changesthat result therefrom.

In various embodiments, a wearable electronic device has amulti-directional input device. The multi-directional input deviceincludes a shaft, a cap operable to move with respect to the shaft, anda sensor coupling the cap to the shaft. The sensor includes an outer setof capacitive elements, an inner set of capacitive elements, adielectric between the outer and inner sets of capacitive elements, anda returning structure. The returning structure is operable to allowmovement of the outer set of capacitive elements with respect to theinner set of capacitive elements and return the outer set of capacitiveelements to a default position. In some examples, the dielectric is thereturning structure

In some examples, a first element of the outer set of capacitiveelements completely overlaps a first element of the inner set ofcapacitive elements. In other examples, a first element of the outer setof capacitive elements is offset from a first element of the inner setof capacitive elements by a first distance and a second element of theouter set of capacitive elements is offset from a second element of theinner set of capacitive elements by a second distance. The first andsecond distances may be different.

In numerous examples, the shaft is fixed. In other examples, the shaftis moveable.

In various examples, the dielectric is at least one of silicone oradhesive. In other examples, the dielectric is an air gap.

In some examples, the electronic device is operable to determinerotation of the cap with respect to the shaft, lateral translation ofthe cap with respect to the shaft, and horizontal translation of the capwith respect to the shaft. The electronic device may determine thesemovements based on capacitance changes between the outer and inner setsof capacitive elements.

In some embodiments, an electronic device has an input device. The inputdevice includes a rotational manipulation mechanism, a first array ofcapacitive elements coupled to the manipulation mechanism, a secondarray of capacitive elements, and a dielectric that couples the firstand second arrays of capacitive elements. The dielectric may operate asa seal for the electronic device. Movement of the manipulation mechanismgenerates capacitance changes between the first and second arrays ofcapacitive elements.

In various examples, the first array of capacitive elements is includedin a first ring. In some implementations of such examples, the secondarray of capacitive elements is included in a second ring that is atleast partially nested within the first ring.

In some examples, movement of the manipulation mechanism may alter atleast one of a first overlap area or a first distance between a firstpair of the first and second arrays of capacitive elements. Movement ofthe manipulation mechanism may also alter at least one of a secondoverlap area or a second distance between a second pair of the first andsecond arrays of capacitive elements. The first overlap area may bedifferent from the second overlap area. The first distance may bedifferent from the second distance.

In numerous examples, the manipulation mechanism is operable to rotate,press, and slide. In various examples, the first array of capacitiveelements has a different number of elements than the second array ofcapacitive elements. In some examples, the first and second arrays ofcapacitive elements may experience a change in capacitance in responseto a touch on the manipulation mechanism.

In numerous embodiments, an input device includes a fixed structure, amoveable member that is rotatable with respect to the fixed structure, afirst set of conductors positioned around the moveable member, and asecond set of conductors positioned around the fixed structure to definea gap between the first and second sets of conductors. Capacitancechanges between the first and second sets of conductors indicatemovement of the moveable element with respect to the fixed structure. Atleast one of the first set of conductors or the second set of conductorsmay be curved.

In some examples, a first conductor of the first set of conductors istransverse to a second conductor of the first set of conductors. Invarious implementations of such examples, a third conductor of the firstset of conductors may be transverse to the second conductor of the firstset of conductors.

In numerous implementations, the input device is a watch crown. In otherimplementations, the input device is a joystick. In yet otherimplementations, the input device may be a variety of different inputdevices.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be readily understood by the following detaileddescription in conjunction with the accompanying drawings, wherein likereference numerals designate like structural elements.

FIG. 1 depicts an electronic device having a multi-directional inputdevice.

FIG. 2A depicts a first example cross-sectional view of themulti-directional input device of FIG. 1, taken along line A-A of FIG.1.

FIG. 2B depicts the multi-directional input device of FIG. 2A duringtranslation.

FIG. 2C depicts a state table illustrating example changes incapacitance of capacitive sensors, with respect to FIGS. 2A and 2B.

FIG. 2D depicts the multi-directional input device of FIG. 2A duringrotation.

FIG. 2E depicts a state table illustrating example changes incapacitance of capacitive sensors, with respect to FIGS. 2A and 2D.

FIG. 3A depicts a second example cross-sectional view of themulti-directional input device of FIG. 2A, where outer and inner sets ofcapacitive elements are offset from each other.

FIG. 3B depicts a state table illustrating example changes incapacitance of capacitors, with respect to FIG. 3A and FIG. 3A with thecap rotated like shown in FIG. 2D.

FIG. 4 depicts a third example cross-sectional view of themulti-directional input device of FIG. 2A where the outer set ofcapacitive elements includes more elements than the inner set ofcapacitive elements.

FIG. 5 depicts a fourth example cross-sectional view of themulti-directional input device of FIG. 2A where the inner set ofcapacitive elements includes more elements than the outer set ofcapacitive elements.

FIG. 6A depicts a second example cross-sectional view of themulti-directional input device of FIG. 1, taken along line B-B of FIG.1.

FIG. 6B depicts the multi-directional input device of FIG. 6A uponexertion of a force that translates the cap in a direction approximatelyperpendicular to the housing.

FIG. 7 depicts another example cross-sectional view of themulti-directional input device of FIG. 6A, where one or more of theouter and inner sets of capacitive elements are offset from each other.

FIG. 8 depicts a fifth example cross-sectional view of themulti-directional input device of FIG. 2A where the dielectric is an airgap and a biasing mechanism.

FIG. 9 depicts a sixth example cross-sectional view of themulti-directional input device of FIG. 2A where the outer ring forms thecap.

FIG. 10 depicts a flow chart illustrating an example method foroperating a capacitive sensor for a directional input device. Thisexample method may be performed by the multi-directional input devicesof FIGS. 1-9.

DETAILED DESCRIPTION

Reference will now be made in detail to representative embodimentsillustrated in the accompanying drawings. It should be understood thatthe following descriptions are not intended to limit the embodiments toone preferred embodiment. To the contrary, it is intended to coveralternatives, modifications, and equivalents as can be included withinthe spirit and scope of the described embodiments as defined by theappended claims.

The description that follows includes sample systems, methods, andapparatuses that embody various elements of the present disclosure.However, it should be understood that the described disclosure may bepracticed in a variety of forms in addition to those described herein.

The following disclosure relates to an input device that incorporates amoveable member. The moveable member can be manipulated in a variety ofdirections to provide input. The input device may also include one ormore capacitive sensors with groups of capacitive elements positionedaround the moveable member. Moving the moveable member may alterpositions of some capacitive elements with respect to others, changingcapacitances therebetween. The capacitance changes may be used togenerate an input signal corresponding to the moveable member's motion.

In a particular embodiment, the sensor may be a ring or partial ring ofcapacitive elements. The capacitive elements may include an outer set ofconductors that is separated from an inner set of conductors by adielectric. Force exerted to move a shaft, cap, or other structurecoupled to the sensor may change the relative position of one or more ofthe sets of conductors with respect to other sets, changing capacitancestherebetween. The dielectric may facilitate the change in relativeposition, and may return the capacitive elements to a default positionafter the force stops.

Various embodiments detect movement in a variety of differentdirections. In some examples, this movement may include translation inone or more directions, rotation, tilt, and so on.

These and other embodiments are discussed below with reference to FIGS.1-10. However, those skilled in the art will readily appreciate that thedetailed description given herein with respect to these Figures is forexplanatory purposes only and should not be construed as limiting.

FIG. 1 depicts an electronic device 100 having a multi-directional inputdevice 102, which may incorporate a capacitive sensor as describedbelow. The multi-directional input device 102 may include a cap 103,crown, or other moveable member or rotational manipulation mechanism.The cap 103 may move in various directions when a user exerts force. Forexample, the cap 103 may rotate with respect to a housing 101 of theelectronic device 100, press by translating horizontally toward and/oraway from the housing 101, slide by laterally translating in one or moredirections approximately parallel to the housing 101, tilt with respectto the housing 101, and so on. The multi-directional input device 102includes one or more capacitive sensors that detect movement of the cap103. Information about the movement may be determined based on one ormore signals received from the capacitive sensor. For example, a type ofmotion, direction of motion, non-binary amount of force applied to causethe motion, and so on may be determined based on various capacitivesensor signals.

FIG. 2A depicts a first example cross-sectional view of themulti-directional input device 102 of FIG. 1, taken along line A-A ofFIG. 1. In this first example, a capacitive sensor includes an outerring 240, including an outer set of capacitive elements 210A-210C (or afirst array of capacitive elements, first set of conductors, and so on)and an inner ring 241, including an inner set of capacitive elements211A-211C (or a second array of capacitive elements, second set ofconductors, and so on). A dielectric 212 separates and couples the outerand inner sets of capacitive elements 210A-210C, 211A-211C, and definesa gap therebetween. The outer set of capacitive elements 210A-210C iscoupled to the cap 103, crown, or other rotational manipulationmechanism and the inner set of capacitive elements 211A-211C is coupledto a fixed shaft 214 or other fixed structure or other component. Theouter and inner rings 240, 241 also include a number of spacers 215, 216(formed of insulating materials such as plastic, polymer, and so on)which respectively isolate the outer and inner sets of capacitiveelements 210A-210C, 211A-211C from each other.

The multi-directional input device 102 may include a returningstructure. The returning structure may allow the outer set of capacitiveelements 210A-210C to move or otherwise alter their position withrespect to the inner set of capacitive elements 211A-211C when the cap103 moves under a force. The returning structure may also return theouter set of capacitive elements 210A-210C to their default positionsafter the exertion of the force. In this example, the returningstructure may be the dielectric 212. The dielectric 212 may be adeformable material, such as silicone or other polymers, suitable gels,foams, adhesive, and so on. The deformable material may allow the outerset of capacitive elements 210A-210C to move or otherwise alter theirposition with respect to the inner set of capacitive elements 211A-211Cand may return the outer set of capacitive elements 210A-210C to theirdefault positions after the exertion of the force.

Movement of the outer set of capacitive elements 210A-210C with respectto the inner set of capacitive elements 211A-211C may changecapacitances therebetween. The capacitance between the outer and innersets of capacitive elements 210A-210C, 211A-211C may be affected by theamount of overlapping area, the distance between the outer and innersets of capacitive elements 210A-210C, 211A-211C, and so on. In a firstexample, the outer set of capacitive elements 210A-210C entirely overlapthe inner set of capacitive elements 211A-211C and are all the samedistance apart. This corresponds to an absence of force exerted on thecap 103. Capacitances, and/or changes in capacitances, between the outerand inner sets of capacitive elements 210A-210C, 211A-211C may bemonitored. Any changes in capacitances (or instantaneous values ofcapacitance) may be analyzed to determine a type of motion of the cap103, direction of motion of the cap 103, non-binary amount of forceapplied to cause the motion of the cap 103, and/or other informationabout motion of the cap 103 with respect to the shaft 214.

Thus, the electronic device 100 (and/or processing unit or othercontroller thereof) may be operable to determine a variety of differentmovements of the cap 103 based on the capacitance changes. Theelectronic device 100 may determine rotation of the cap 103 with respectto the shaft 214 in one or more directions. The electronic device 100may also determine translation of the cap 103 laterally and horizontally(in reference to FIG. 2A) with respect to the shaft 214 (e.g., in atleast two transverse planes, such as a plane parallel to the housing 101and a plane perpendicular to the housing 101).

The configuration of this first example multi-directional input device102 may use a relatively small number of components without introducingexcessive complexity. Further, the configuration of this first examplemulti-directional input device 102 may allow watertight ornear-watertight sealing between the multi-directional input device 102and the housing 101, restricting the passage of contaminants such asdust or liquid. In some implementations, the dielectric 212 and/or thesensor itself may function as such a seal or gasket. In otherimplementations, other seals, gaskets, and so on may also be included.

In some implementations, the outer set of capacitive elements 210A-210Cmay be drive elements and the inner set of capacitive elements 211A-211Cmay be sense elements. In other implementations, the drive and senseelements may be reversed. In still other implementations, the drive andsense elements may be intermixed among the outer and inner sets ofcapacitive elements 210A-210C, 211A-211C. In various implementations,drive elements may be passive.

In this example, the outer and inner sets of capacitive elements210A-210C, 211A-211C are curved. Further, the outer and inner sets ofcapacitive elements 210A-210C, 211A-211C are positioned in multipleplanes around the cap 103 in complete rings 240, 241, where the innerring 241 is at least partially nested within the outer ring 240. Forexample, the outer capacitive element 210C is transverse to the outercapacitive element 210A (e.g., two different planes), which is itselftransverse to the outer capacitive element 210B (e.g., a third plane).However, it is understood that this is an example. In variousimplementations, various capacitive elements may be positioned indifferent configurations without departing from the scope of the presentdisclosure, and/or may have any of a variety of shapes. For example, insome implementations, the outer and inner sets of capacitive elements210A-210C, 211A-211C may be configured in partial rings rather than thecomplete outer and inner rings 240, 241 shown.

Lateral motion of the cap 103 in a direction 230, or slide motion of thecap 103, will now be described in detail. FIG. 2B depicts themulti-directional input device 102 upon exertion of a force applied by auser 217. This force laterally translates the cap 103 in the direction230 approximately parallel to the housing 101. Lateral translationcauses the outer capacitive element 210A to shift with respect to theinner capacitive element 211A such that they are the same distance apartbut have less overlapping area. Lateral translation also causes theouter capacitive element 210B to move apart from the inner capacitiveelement 211B such that they have the same overlapping area but thedistance between has increased. Further, lateral translation causes theouter capacitive element 210C to approach the inner capacitive element211C such that the overlapping area is the same but the distance betweenhas decreased.

FIG. 2C depicts a state table illustrating example changes incapacitance between the outer and inner sets of capacitive elements210A-210C, 211A-211C between the states shown in FIGS. 2A and 2B. Thecapacitances between the outer and inner sets of capacitive elements210A-210C, 211A-211C in FIG. 2A are all the same value (represented as“X”) because all of outer and inner sets of capacitive elements210A-210C, 211A-211C are the same distance apart and have the sameoverlapping area. However, in FIG. 2B, the decreased overlapping areabetween the outer capacitive element 210A and the inner capacitiveelement 211A results in a first changed capacitance less than X.Further, the increased distance between the outer capacitive element210B and the inner capacitive element 211B results in a second changedcapacitance that is also less than X. Typically, although notnecessarily, the values of the first and second changed capacitances aredifferent. Additionally, the decreased distance between the outercapacitive element 210C and the inner capacitive element 211C results ina third changed capacitance that is greater than X.

These three changed capacitances may be analyzed and compared to eachother. Based thereon, the electronic device 100 may determine that thecap 103 has laterally translated in the direction 230 shown in FIG. 2B.The electronic device 100 may also determine the non-binary amount ofthe force that caused the motion based on the magnitude of thecapacitance changes and/or other capacitance change factors.

Although the above describes relative evaluation by looking atcapacitive changes to determine motion, it is understood that this is anexample. In some implementations, an absolute evaluation of a currentcapacitance may be used to determine movement without reference to aninitial capacitance.

The electronic device 100 may analyze and compare the changedcapacitances, or capacitance changes, in a variety of ways. For example,the electronic device 100 may consult one or more lookup tables storedin a non-transitory media in order to correlate the capacitance changesto various types of motion, direction of motion, amount of motion,amount of force, and so on. For example, decreased capacitance on onlyone side may indicate lateral motion in the opposite direction. By wayof another example, decreased capacitance seen by all capacitiveelements may indicate rotation.

FIG. 2B depicts left/right, with reference to FIG. 2B, lateral or slidemotion of the cap 103. The cap 103 may also move laterally up/down (withreference to FIG. 2B) and this motion may be detected based oncapacitances between the outer and inner sets of capacitive elements210A-210C, 211A-211C. This lateral up/down motion may operate similarlyto the left/right lateral motion described above. However, in someimplementations, the two motions may be recognized as different types ofinput. In various implementations, different types of input may berecognized for each different way that the FIG. 2B depicts left/right,with reference to FIG. 2B, lateral or slide motion of the cap 103. Thecap 103 may also move laterally up/down (with reference to FIG. 2B) andthis motion may be detected based on capacitances between the outer andinner sets of capacitive elements 210A-210C, 211A-211C may move withrespect to each other.

Rotation of the cap 103 will now be described in detail. FIG. 2D depictsthe multi-directional input device 102 of FIG. 2A upon exertion of aforce applied by a user 217 that rotates the cap 103 in a direction 231.This rotation causes all of the outer capacitive elements 210A-210C toshift with respect to the respective inner capacitive elements 211A-211Csuch that they are the same distance apart but have less overlappingarea 232A-232C. FIG. 2E depicts a state table illustrating examplecapacitances between the outer and inner sets of capacitive elements210A-210C, 211A-211C, as they are in the state shown in FIG. 2A and inthat of FIG. 2D. As discussed above with respect to FIG. 2C, thecapacitances between the outer and inner sets of capacitive elements210A-210C, 211A-211C in FIG. 2A are all the same value, namely X.However, in FIG. 2D, the decreased overlapping area 232A-232C betweenthe outer capacitive elements 210A-210C and the respective innercapacitive elements 211A-211C results in capacitances that are all lessthan X. These capacitances may be analyzed and compared to each other.Because all three capacitances decrease, the electronic device 100 maydetermine that the cap 103 has rotated.

In this example, the capacitance changes between the outer and innercapacitive elements 210A-210C, 211A-211C are entirely caused by thechanging overlapping area 232A-232C due to rotation. In such asituation, the capacitance changes may not indicate the direction of therotation as the same amount of rotation in either direction would resultin the same change in overlapping area. However, a force exerted torotate the cap 103 may also translate the cap 103 in a directionopposite the direction of the applied force, at least minimally. Assuch, gaps (distances) between one or more of the outer and innercapacitive elements 210A-210C, 211A-211C would change and the threecapacitance changes would not be precisely identical. These differencesbetween the three capacitances may be analyzed in order to determine thedirection of the rotation based on where the gaps are increasing and/ordecreasing.

In other implementations, other configurations may be utilized thatresult in different capacitance changes for different directions ofrotation. For example, FIG. 3A depicts a second example cross-sectionalview of the multi-directional input device 102 of FIG. 2A where a numberof the outer and inner sets of capacitive elements 310A-310C, 311A-311Care offset from each other (e.g., from the respective associatedcapacitive element 310A-310C, 311A-311C). In this example, the outercapacitive element 310A is offset from the inner capacitive element 311Ain a first direction 331 by a first distance whereas the outercapacitive element 310B is offset from the inner capacitive element 311Bin an opposite direction 333 by a second distance. The first and seconddistances may be different. Thus, the capacitive elements 310A, 311A areoffset differently than the capacitive elements 310B, 311B.

As a result, the overlapping area (and thus the capacitance) between theouter capacitive element 310A and the inner capacitive element 311Adecreases if the cap 303 was rotated in the direction 331 and increasesif the cap 303 was rotated in the opposite direction 333. Conversely,the overlapping area (and thus the capacitance) between the outercapacitive element 310B and the inner capacitive element 311B increasesif the cap 303 was rotated in the direction 331 and decreases if the cap303 was rotated in the opposite direction 333. Thus, the threecapacitance changes may be analyzed to determine the rotation of the cap303, the amount of rotation, and the direction of rotation.

FIG. 3B depicts a state table illustrating example changes incapacitance between the outer and inner sets of capacitive elements310A-310C, 311A-311C between the state shown in FIG. 3A and the statewhen the cap 303 is rotated in the direction 331. The capacitancesbetween the outer and inner sets of capacitive elements 310A-310C,311A-311C in FIG. 3A are all different values (represented by “Y,” “Z,”and “X”) because all of the outer and inner sets of capacitive elements310A-310C, 311A-311C have different overlapping areas. However, uponrotation like shown in FIG. 2D, the further decreased overlapping areabetween the outer capacitive element 310A and the inner capacitiveelement 311A results in a capacitance less than Y. Conversely, theincreased overlapping area between the outer capacitive element 310B andthe inner capacitive element 311B results in a capacitance greater thanZ. The decreased overlapping area between the outer capacitive element310C and the inner capacitive element 311C is the same as in FIG. 2A,less than X.

Although FIGS. 3A-3B illustrate an example configuration that results indifferent capacitance changes for different directions of rotation,other configurations are possible. For example, FIG. 4 depicts a thirdexample cross-sectional view of the multi-directional input device 102of FIG. 2A where the outer set of capacitive elements 410A-410D includesmore elements than the inner set of capacitive elements 411A-411C.

In this third example, the additional capacitive element 410D may not(or may minimally) capacitively couple with any of the inner set ofcapacitive elements 411A-411C. However, when the cap 403 is rotated inthe direction 431, the capacitive element 410D and the capacitiveelement 411A may capacitively couple as they begin to overlap. Based onthis capacitive change, combined with the decreases in capacitancebetween the outer and inner sets of capacitive elements 410A-410C,411A-411C due to the decreased overlap area between those elements, theelectronic device 100 may determine that the cap 403 has rotated in thedirection 431.

Conversely, when the cap 403 is rotated in the opposite direction 433,the capacitive element 410D may capacitively couple with the capacitiveelement 411C. As such, this capacitive change, combined with thedecreases in capacitance between the outer and inner sets of capacitiveelements 410A-410C, 411A-411C due to the decreased overlap area betweenthose elements, indicates the rotation of the cap 403 in the oppositedirection.

By way of another possible configuration, FIG. 5 depicts a fourthexample cross-sectional view of the multi-directional input device 102of FIG. 2A where the inner set of capacitive elements 511A-511D includesmore elements than the outer set of capacitive elements 510A-510C. Inthis fourth example, the capacitive element 511D may not (or mayminimally) capacitively couple with any of the outer set of capacitiveelements 510A-510C. However, when the cap 503 is rotated in thedirection 531, the capacitive element 511D and the capacitive element510A may capacitively couple as they begin to overlap. Based on thatcapacitive change, combined with the decreases in capacitance betweenthe outer and inner sets of capacitive elements 510A-510C, 511A-511C dueto the decreased overlap area between those elements, the electronicdevice 100 may determine that the cap 503 has rotated in the direction531.

Conversely, when the cap 503 is rotated in the opposite direction 533,the capacitive element 511D may overlap the capacitive element 510B. Assuch, the capacitive element 511D and the capacitive element 510B maycapacitively couple. This capacitance change, combined with thedecreases in capacitance between the outer and inner sets of capacitiveelements 510A-510C, 511A-511C due to the decreased overlap area betweenthose elements, indicates the rotation of the cap 503 in the oppositedirection 533.

FIG. 6A depicts a second example cross-sectional view of themulti-directional input device 102 of FIG. 1, taken along line B-B ofFIG. 1. As shown, one or more of the outer and inner sets of capacitiveelements 210A-210C, 211A-211C may be connected to the electronic device100 (and/or a component thereof, such as a processing unit or othercontroller) via flex circuits 218A, 218B and/or other conductivematerials or communication connections. FIG. 6B depicts themulti-directional input device 102 of FIG. 6A upon exertion of a forceby a user 217 that horizontally translates the cap 103 (e.g., in adirection 634 approximately perpendicular to the shaft 214). Horizontaltranslation of the cap 103 corresponds to a press motion. In thisexample, the cap 103 horizontally translates toward the shaft 214 andthe housing.

Horizontal translation of the cap 103 toward the housing changes theposition of the outer and inner sets of capacitive elements 210A-210C,211A-211C with respect to each other as well as spacers 215, 216. Thespacers 215, 216 are also separated by the dielectric 212, and may beomitted in some embodiments. Due to the relative change in positionbetween the outer and inner sets of capacitive elements, thecapacitances decrease because the overlapping area decreases. As such,the electronic device 100 may determine from the capacitance changesthat the cap 103 has horizontally translated in a direction 634approximately perpendicular to the housing 101.

However, as all of the outer and inner sets of capacitive elementschange relative position by the same amount, the capacitance changes maybe the same whether the cap 103 horizontally translates by the sameamount toward or away from the housing. In various otherimplementations, the outer and inner sets of capacitive elements210A-210C, 211A-211C may be configured such that capacitances changedifferently between the outer and inner sets of capacitive elementsdepending on whether the cap 103 moves toward or away from the housing101. Such configurations may include offsetting one or more of the outerand inner sets of capacitive elements 210A-210C, 211A-211C with respectto each other, such as in the horizontal direction 634 (e.g.,approximately perpendicular to the housing 101) and similar to theoffsets depicted in the example of FIGS. 3A-3B.

For example, FIG. 7 depicts another example cross-sectional view of themulti-directional input device 102 of FIG. 6A where one or more of theouter and inner sets of capacitive elements 710A-710C, 711A-711C arehorizontally offset from each other. As shown, the capacitive elements710A, 711A are offset in a direction 734. As such, the capacitancebetween them will change differently depending on whether the cap 703horizontally translates toward the shaft 714 or away from the shaft 714.In some implementations, one or more other of the outer and inner setsof capacitive elements 710B-710C, 711B-711C may be offset from eachother, and may be offset differently than the capacitive elements 710A,711A.

Although FIG. 7 illustrates an example configuration that results indifferent capacitance changes for translation toward and away from thehousing 101, other configurations are possible. For example, one or moreof the outer and inner sets of capacitive elements 710A-710C, 711A-711Cmay include one or more additional capacitive elements disposed closerto or further from the housing 101 than the outer and inner sets ofcapacitive elements 710A-710C, 711A-711C similar to the configurationsdepicted in the examples of FIGS. 4-5.

Additionally or alternatively, multiple rows of outer and inner sets ofcapacitive elements 210A-210C, 211A-211C may be utilized rather than thesingle row of outer and inner sets of capacitive elements 210A-210C,211A-211C shown in FIGS. 2A and 6A-6B. In some examples, two rows ofouter and inner sets of capacitive elements 210A-210C, 211A-211C may bepositioned and separated from each other in the direction 634 such thatthe first row is closer to the housing 101 in the direction 634 than thesecond row. This may allow detection of whether the cap 103 movestowards or away from the shaft 214 based on capacitances between theouter and inner sets of capacitive elements 210A-210C, 211A-211C of thefirst and second rows. For example, the first row of the outer and innersets of capacitive elements 210A-210C, 211A-211C and the second row ofthe outer and inner sets of capacitive elements 210A-210C, 211A-211C mayeach capacitively couple absent movement of the cap 103 towards or awayfrom the shaft 214. However, these capacitances may decrease as the cap103 moves towards or away from the shaft 214. Further, the outercapacitive elements 210A-210C of the first row may begin to capacitivelycouple with the inner capacitive elements 211A-211C of the second rowwhen the cap 103 moves away from the housing 101. Similarly, the outercapacitive elements 210A-210C of the second row may begin tocapacitively couple with the inner capacitive elements 211A-211C of thefirst row when the cap 103 moves toward from the housing 101.

Additionally, first and second rows of outer and inner sets ofcapacitive elements 210A-210C, 211A-211C may provide multiple sets ofcapacitances to evaluate. This may provide greater resolution indetermining rotation, lateral translation, horizontal translation, andpress of the cap 103 with respect to the housing 101.

Moreover, first and second rows of outer and inner sets of capacitiveelements 210A-210C, 211A-211C may enable detection of tilt of the cap103. If a force is exerted to tilt the cap 103 at an angle other thanparallel or perpendicular with respect to the shaft 214, capacitancesbetween some of the first and second rows of the outer and inner sets ofcapacitive elements 210A-210C, 211A-211C would increase due to increasedproximity and/or overlap whereas capacitances between others woulddecrease due to decreased proximity and/or overlap. As the capacitancechanges would be different depending on the direction in which the cap103 was tilted, the capacitance changes may be evaluated to determinethe direction and/or amount of the tilt.

FIG. 2A is illustrated and described as including a dielectric 212 thatis a deformable material, such as silicone, adhesive, and so on.However, in other implementations, other dielectrics 212 may be usedthat may operate differently. For example, FIG. 8 depicts a fifthexample cross-sectional view of the multi-directional input device 102of FIG. 2A where the dielectric is an air gap 819 and the deviceincorporates a biasing mechanism 820.

In this fifth example, the outer and inner sets of capacitive elements810B-810C, 811B-811C are not directly connected. Instead, they areseparated by the air gap 819. Biasing mechanisms 820, such as springs orother elastic elements, couple the spacers 815 and 816. In this example,the biasing mechanisms 820 may be the returning mechanism. The biasingmechanisms 820 bias the outer and inner sets of capacitive elements810B-810C, 811B-811C in the position shown and operate to return theouter and inner sets of capacitive elements 810B-810C, 811B-811C to theposition shown when a force exerted on the cap 803 changes theirposition.

Further, FIG. 2A is illustrated and described with the cap 103 beingseparate from the outer ring 240 including the outer set of capacitiveelements 210A-210C. However, in various implementations, the cap 103 maybe omitted. For example, FIG. 9 depicts a sixth example cross-sectionalview of the multi-directional input device 102 of FIG. 2A where theouter ring forms the cap 903.

In this example, the outer ring of the sensor may be directlymanipulated by a user to move with respect to the housing 101. As theuser or other object contacts the outer ring of the sensor, the user maydirectly contact one or more of the outer set of capacitive elements910A-910C. This may influence the capacitances between the outer andinner sets of capacitive elements 910B-910C, 911B-911C. The electronicdevice 100 may analyze the capacitance changes caused by the usercontacting one or more of the outer set of capacitive elements 910A-910Cin order to determine various characteristics of movement of the cap903.

For example, the outer set of capacitive elements 910A-910C may be senseelements. As such, contact by the user with one or more of the outer setof capacitive elements 910A-910C may short the respective element. Basedon the detected short, the electronic device 100 may determine a touchlocation, or where the user is touching the cap. The electronic device100 may scale and/or otherwise vary how the electronic device 100interprets the capacitive changes between the outer and inner sets ofcapacitive elements 910B-910C, 911B-911C based on the detected touchlocation.

For example, if analysis of the capacitive changes could indicatetranslation in two opposing directions, the electronic device 100 maydetermine the cap has translated in the direction opposite the touchlocation. This is because a user would likely have been unable to movethe cap without pushing on the cap from the opposing side.

Additionally, the multi-directional input device 102 of FIG. 2A isdescribed as having a fixed shaft 214. However, in variousimplementations, the shaft 214 may be operable to move in one or moredirections. In some implementations, the shaft 214 may be operable tospin freely. In other implementations, the shaft 214 may be operable tomove in response to an additional force exerted on the cap 103 that isgreater than the force that moves the outer and inner sets of capacitiveelements 910B-910C, 911B-911C.

For example, the shaft 214 may be frictionally mounted, such as withbearings. The frictional mounting may resist more force than does thedielectric 212. The outer and inner sets of capacitive elements910B-910C, 911B-911C may move with respect to each other under a lesseramount of force than moves the shaft 214. In other words, the outer andinner sets of capacitive elements 910B-910C, 911B-911C may move withrespect to each other when a force is exerted. When the force increasessufficiently to also move the shaft 214, the shaft 214 may also move.

FIG. 2A is illustrated and described as a watch crown or similarmulti-directional input device 102. However, it is understood that thisis an example. In other implementations, the techniques discussed hereinmay be used with a variety of different input and/or output mechanisms.

For example, a joystick or similar rotational or other input mechanismmay include a sensor (such as the one depicted in FIG. 2A) which may bepositioned around a shaft (like the shaft 214 in FIG. 2A) that ismoveable with respect to a fixed outer element (positioned similarly tothe cap 103 in FIG. 2A). Movement of the shaft with respect to the fixedouter element may alter the position of the first and second arrays orsets of capacitive elements or conductors. As such, capacitivedifferences between the first and second arrays or sets of capacitiveelements or conductors may be analyzed and compared to determinemovement of the shaft.

By way of another example, a track ball or similar rotational or otherinput mechanism may include a sensor positioned around a moveablemechanism, such as a sphere or similar element. The sphere may bemoveable with respect to a fixed outer element. Movement of the spherewith respect to the fixed outer element, which may be omnidirectional insome implementations, may alter the position of first and second arraysor sets of capacitive elements or conductors, altering capacitivedifferences that may be analyzed and compared to determine movement ofthe sphere.

FIG. 2A is illustrated and described as a multi-directional input device102 that includes capacitive sensors. However, it is understood thatthis is an example. In other implementations, other kinds of sensors,such as strain gauges, may be used without departing from the scope ofthe present disclosure.

Further, FIG. 2A is illustrated and described as the outer and innersets of capacitive elements 210A-210C, 211A-211C being curved and beingcomponents of outer and inner rings 240 and 241. However, in variousimplementations, the outer and inner sets of capacitive elements210A-210C, 211A-211C may be otherwise configured. For example, the outerand inner sets of capacitive elements 210A-210C, 211A-211C may be flatand may be components of square or other shaped elements rather than theouter and inner rings 240 and 241.

FIG. 10 depicts a flow chart illustrating an example method 1000 foroperating a capacitive sensor for a directional input device. Thisexample method 1000 may be performed by the multi-directional inputdevices of FIGS. 1-9.

At 1010, capacitances between one or more of an outer layer ofcapacitive elements and an inner layer of capacitive elements may bemeasured. The layers of capacitive elements may be operable to move withrespect to each other based on force exerted on an input mechanism.Movement of the layers of capacitive elements with respect to each othermay alter the capacitances.

At 1020, it may be determined whether or not the capacitances havechanged. This determination may be performed by a processing unit orother controller that receives signals from a sensor which includes thelayers of capacitive elements. If not, the flow returns to 1010 wherethe capacitances continue to be measured. Otherwise, the flow proceedsto 1030.

At 1030, the various capacitance changes are analyzed and/or compared todetermine movement between the outer and inner layers of capacitiveelements. This analysis and/or comparison may be performed by aprocessing unit or other controller. Movement of an input mechanismassociated with the layers of capacitive elements may be determinedbased on the movement of the layers of capacitive elements.

Although the example method 1000 is illustrated and described asincluding particular operations performed in a particular order, it isunderstood that this is an example. In various implementations, variousorders of the same, similar, and/or different operations may beperformed without departing from the scope of the present disclosure.

For example, in some implementations, the example method 1000 mayinclude the additional operation of determining a non-binary amount ofthe force that was applied to cause the movement of the layers ofcapacitive elements. In such implementations, the non-binary amount ofapplied force may be determined based on the capacitance changes.

By way of another example, the layers of capacitive elements aredescribed as outer and inner layers of capacitive elements. However, invarious implementations, first or second sets or arrays of capacitiveelements or other conductors may be utilized in configurations that arenot “outer” or “inner” with respect to each other. In someimplementations, the first or second sets or arrays of capacitiveelements or other conductors may be adjacent rather than nested orotherwise similarly situated.

Returning to FIG. 1, the electronic device 100 is shown as a wearableelectronic device including a display that is coupleable to a user usinga band or other attachment mechanism. However, it is understood thatthis is an example. In various implementations, the electronic device100 may be any kind of electronic device without departing from thescope of the present disclosure. For example, the electronic device 100may be a laptop computing device, a smart phone, a desktop computingdevice, a mobile computing device, a display, a cellular telephone, adigital media player, a fitness monitor, a printer, a tablet computingdevice, and so on.

Further, the electronic device 100 may include additional components notshown without departing from the scope of the present disclosure. Invarious examples, the electronic device 100 may include one or moreprocessing units, communication components, sensors, non-transitorystorage media (which may take the form of, but is not limited to, amagnetic storage medium; optical storage medium; magneto-optical storagemedium; read only memory; random access memory; erasable programmablememory; flash memory; and so on), input/output components, and so on.

As described above and illustrated in the accompanying figures, thepresent disclosure relates to a capacitive sensor for a directionalinput device. The input device may include a moveable member that can bemanipulated to provide input. The input device may also include one ormore sensors with groups of capacitive elements configured in multipleplanes around the moveable member. Movement of the moveable member mayalter positions of various of the groups of capacitive elements withrespect to each other, changing capacitances therebetween. Informationabout that movement may then be determined based at least on thecapacitance changes.

In the present disclosure, the methods disclosed may be implemented assets of instructions or software readable by a device. Further, it isunderstood that the specific order or hierarchy of steps in the methodsdisclosed are examples of sample approaches. In other embodiments, thespecific order or hierarchy of steps in the method can be rearrangedwhile remaining within the disclosed subject matter. The accompanyingmethod claims present elements of the various steps in a sample order,and are not necessarily meant to be limited to the specific order orhierarchy presented.

The foregoing description, for purposes of explanation, used specificnomenclature to provide a thorough understanding of the describedembodiments. However, it will be apparent to one skilled in the art thatthe specific details are not required in order to practice the describedembodiments. Thus, the foregoing descriptions of the specificembodiments described herein are presented for purposes of illustrationand description. They are not targeted to be exhaustive or to limit theembodiments to the precise forms disclosed. It will be apparent to oneof ordinary skill in the art that many modifications and variations arepossible in view of the above teachings.

What is claimed is:
 1. A wearable electronic device comprising: amulti-directional input device comprising: a shaft; a cap operable tomove with respect to the shaft; a sensor coupling the cap to the shaftand comprising: an outer set of capacitive elements; and an inner set ofcapacitive elements; and a returning structure operable to: in responseto a force applied to the cap, allow movement of the outer set ofcapacitive elements with respect to the inner set of capacitiveelements; and in response to the force being removed from the cap,return the outer set of capacitive elements to a default position. 2.The wearable electronic device of claim 1, wherein a first element ofthe outer set of capacitive elements completely overlaps a first elementof the inner set of capacitive elements.
 3. The wearable electronicdevice of claim 1, wherein a first element of the outer set ofcapacitive elements is offset from a first element of the inner set ofcapacitive elements.
 4. The wearable electronic device of claim 3,wherein: the first element of the outer set of capacitive elements isoffset from the first element of the inner set of capacitive elements bya first distance; a second element of the outer set of capacitiveelements is offset from a second element of the inner set of capacitiveelements by a second distance; and the first and second distances aredifferent.
 5. The wearable electronic device of claim 1, wherein theshaft is moveable.
 6. The wearable electronic device of claim 1, furthercomprising a dielectric positioned between the outer and inner sets ofcapacitive elements.
 7. The wearable electronic device of claim 6,wherein the dielectric comprises at least one of silicone, an adhesive,or an air gap.
 8. The wearable electronic device of claim 6, wherein thedielectric is the returning structure.
 9. The wearable electronic deviceof claim 1, wherein the wearable electronic device is operable todetermine rotation of the cap with respect to the shaft, lateraltranslation of the cap with respect to the shaft, and horizontaltranslation of the cap with respect to the shaft based on capacitancechanges between the outer and inner sets of capacitive elements.
 10. Anelectronic device, comprising: an input device comprising: a rotationalmanipulation mechanism; a first array of capacitive elements coupled tothe rotational manipulation mechanism; a second array of capacitiveelements; and a dielectric positioned between the first and secondarrays of capacitive elements; wherein: the electronic device isoperable to determine either a linear translation or a rotation of therotational manipulation mechanism based on a change in capacitancebetween the first and second arrays of capacitive elements.
 11. Theelectronic device of claim 10, further comprising: a first ringcomprising the first array of capacitive elements disposed in a firstcircular pattern; and a second ring comprising the second array ofcapacitive elements disposed in a second circular pattern.
 12. Theelectronic device of claim 10, wherein the dielectric operates as a sealfor the electronic device.
 13. The electronic device of claim 10,wherein the rotational manipulation mechanism is configured to rotate ortranslate in response to a force applied to the rotational manipulationmechanism.
 14. The electronic device of claim 10, wherein the firstarray of capacitive elements has a different number of elements than thesecond array of capacitive elements.
 15. The electronic device of claim10, wherein the first and second arrays of capacitive elementsexperience the change in capacitance in response to a touch on therotational manipulation mechanism.
 16. An input device comprising: arotational manipulation mechanism; a first array of capacitive elementscoupled to the rotational manipulation mechanism; a second array ofcapacitive elements; and a dielectric positioned between the first andsecond arrays of capacitive elements; wherein: movement of therotational manipulation mechanism results in a change in a first overlaparea between a first pair of the first and second arrays of capacitiveelements and movement of the rotational manipulation mechanism resultsin a change in a second overlap area between a second pair of the firstand second arrays of capacitive elements, the first overlap area beingdifferent from the second overlap area.
 17. The input device of claim16, wherein at least one of the first array of capacitive elements orthe second array of capacitive elements is curved.
 18. The input deviceof claim 16, wherein the input device comprises a watch crown.
 19. Anelectronic device having an input device, the input device comprising: amanipulation mechanism; a first array of capacitive elements coupled tothe manipulation mechanism; a second array of capacitive elementsseparated from the first array of capacitive elements; and a dielectricpositioned between the first and second arrays of capacitive elements;wherein: movement of the manipulation mechanism results in a change in afirst distance between a first pair of the first and second arrays ofcapacitive elements; movement of the manipulation mechanism results in achange in a second distance between a second pair of the first andsecond arrays of capacitive elements; and the first distance isdifferent from the second distance.
 20. The electronic device of claim19, wherein the input device comprises a joystick.